“Solar power” photovoltaic cells have been used to charge and power various consumer electronic devices since the introduction of the solar-powered handheld calculators in the late 1970s. A portion of the face of such devices was dedicated to the photovoltaic cells. However, in today's mobile phones and tablet computers, surface area is at a premium, leaving no space on the front of the device to dedicate in any meaningful way to photovoltaic cells. As a result, solar chargers for phones and tables are offered as external add-ons to be connected by cable or mounted on the back of the device, reducing the utility and convenience of charging the device using ambient light.
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